What is BMI?

Body mass index (BMI) is considered the best measure for overweight.

There are several reasons for this:

BMI can be used by both children and adults.
BMI is independent of height and can therefore be used by both high and low people.
The higher BMI, the more body fat you have.
The higher BMI, the more often you become ill.
The higher BMI, the higher risk you have of an earlier death

You can easily calculate your own BMI:

The persons weight in kg / the persons height in metres * the persons height in metres.
If you weigh 90 kg, are 1,8 metre tall, your BMI is = 90 / 1,8 * 1,8 = 27,8.
If you weigh 100kr, are 1,8 metres tall, your BMI is = 100 / 1,8 * 1,8 = 30,9.

BMI has been measured with many thousands of people and thereafter it has been established when a BMI is too high. BMI changes with age.
With adults, the BMI increases until you are middle aged. There is a big difference between BMI with the smallest children and the slightly larger children.